Annealing furnace structure



C. B. HOAK 'ANNEALING FURNACE STRUCTURE April 2, 1940.

Filed March 3, 1936 4 Sheets-Sheet 1 Inventor v F I April 1940- c. B. HOAK 2,196,167

ANNEALING FURNACE STRUCTURE Filed March 5, 1936 4 Sheets-Sheet 2 I 5 My /Z v Z 3 [mien [or I 4 f C B-fiomk 32 4 Anna Attorneys April 2, 1940. c, B, HOAK 2,196,167

ANNEALING FURNACE STRUCTURE Filed March 3, 1936 4 Sheets-Sheet 3 lnvenlor a g v 5 A Home Patented Apr. 2, 1940 UNITED STATES PATENT OFFICE My invention relates generally to annealing' furnace structure especially adapted to the heat treating ofsheet steel and tin and incorporating special features insuring proper distributionof the heat to the top, bottom, and sides of the material while in the annealing chamber, and in a manner to positively prevent oxidizing of the ma-' terial being annealed, and an important object of the present invention is to provide annealing structure of the character indicated whereby either a sectional or an integral annealing furnace may be constructed and operated efllciently, either the furnace as a whole or the sections thereof being readily portable by suitable cranes or hoists, and transported from place to place as needed.

Another important object of the present invention is to provide improvements in structure and in function over the subject matter set forth in .my co-pending application Serial No. 26,049, filed June 11, 1935, now Patent No. 2,040,994 dated May 19, 1936, and entitled Annealing furnace, in the regards of better and more efficient provision for circulation of and use of the heating gas- 1 es and products of combustion, in better use of the heat through provision of heat absorbing and radiating partitions between the combustion chambers and the annealing chamber, and in providing improved materials for the partitions as well as more efflcient structure thereof, and other provisions which will appear in the following description of the drawings.

Another important object of the invention is'to provide partition means defining the combustion chambers and the annealing chamber which not' only act as conduits for the gases and products of combustion from the burners, but act as means to radiate heat into the annealing chamber, by conduction and convection to increase the use of the heat generatedby the burners-in the combustion chambers and produce better distribution of the heat in the annealing chamberi by providing sectional partition structure in which the sections have thinner walls with smaller overlapping portions and greater surfaces in contact with the products of combustion in the combustion chambers and with the atmosphere in the annealing chamber: the said sections beingarranged and placed with respect to each other to allow for expansion and contraction.

Other important objects of the present invention will be apparent from a reading of the following description in connection with the drawings, wherein for purposes of illustration 1 have lustrated in Figure 3.

shown preferred embodiments of the present invention. p

The present application constitutes a continuation in part of the co-pending application mentioned above.

In the drawings: I

Figure 1 is a general side elevational view of one embodiment of my invention.

Figure 2 is a transverse vertical sectional view taken through Figure 4 approximately on. the line 10 Figure 3 is a horizontal sectional view taken through Figure 1 approximately on the line 3-4 and looking downwardly in the direction of the arrows. 15

Figure 4 is a transverse vertical sectional view taken through Figure 1 or 2 approximately on the line 4-4 and showing the hood without the base.

Figure 5 is an elevational view of one of the partition sections. v

Figure 6 is a transverse vertical sectional view taken through Figure 5 approximately on the line 8-6.

Figure 7 is a top plan view of Figure 6.

Figure 8 is a group horizontal sectional view showing adjacent partition sections and illustrating the manner in which they inter-engage to form the partition.

7 Figure 9 is a perspective view of one of the covers.

Figure 10 is a bottom plan view of one of the platforms.

Referring in detail to the drawings, the numeral 5 generally designates the hood of the furnace which may be cruciform in plan and dome-shaped in cross section as shown or assume any other suitable size and shape and be composed of an outer metal shell 6 having a hoisting handle 1 at its top and have inwardly extending from its lower edges the annular flange 8 which rests on the floor of the base Ill, so that the hood is thereby separable from the base and can be lifted therefrom. Burner openings ii are distributed circumferentially around the lower side I walls of the hood,'an'y suitable number of these burner openings I! being located in each arm or wing-1'2 of the hood which has, the cruciform or other suitable shaped horizontal cross" section -1l:- Each arm I2 of the hood has its interior lined with suitable refractory material structure, the; walls of which are severally and respectively designated by the numerals l3, l4, l5 and I0, being the opposite side walls, the radially outward wall, 56

and the bottom wall. The radially outward wall l5 arches across the top of the shell and forms the top boundary of the annealing chamber as well as of the respective combustion chambers defined by the mentioned walls and the respective partitions each of which is generally designated l'l.

Each partition is composed of a plurality of tiers in side by side relation, each tier being composed of vertically superposed sections l8, l9 and 20, and a desirable number of tiers is used in each partition H, the tiers being juxtaposed and interlocked in a manner to be pointed out.

Each of the tier sections is in the form of a body of heat resisting metal or of refractory material suitable to radiate and conduct heat from the combustion chamber to material being heated, the body being triangular in cross-section 2| having a triangular cross-section bore 22 defining relatively thin acutely angulated walls 23 and 24 and the annealing chamber wall 25 which in the case of the upper and lower sections i8 and 20, respectively, have at the proper level the gas passing openings 26 and 21 and between them the solid part having the vertical bore 28 which is provided to receive the assembling bolt 29 which has a head 30 embedded in the lower end of the bottom tier section on a level with the lower gas passages 52 and a threaded upper portion passing through a boss 3! on the upper side of the shell 6, as shown in Figure 4, and accommodating a nut arranged to bear against the top of the boss 3|.

The lower tier section i8 is provided in its top with a socket telescopically receiving the reduced portion 32 on the lower end of the intermediate tier section l9; and the section l9 has a socket 33 in its upper end receiving the reduced lower end of the upper tier section 20. The lower end of the lower tier section I8 is squared, while the upper end of the upper section 20 is beveled to conformably' engage the inner surface of the refractory wall l5.

One end of the wall 25 of each of the sections is pointed as indicated by the numeral 35 while the opposite end is notched as indicated by the numeral 36, both formations extending the full height of the respective section. The points 35 are engaged with the notches 36 in juxtaposing and assembling the various tiers of sections to form the respective partitions I1.

The base l has within the annealing chamber defined by .the radially inward sides of the described tiers the raised refractory material transverse generally parallel portions 31 and 38, thereby defining two separate supports for the annealing stands with a transverse passage therebetween which has therealong a plurality of vertical exhaust outlet openings 39 whichtraverse the base as indicated in Figure 2. Any suitable number of annealing stands may be used with corresponding obvious rearrangements and enlargements of the base and hood structure.

Imposed on each platform 31, 33 is an annealing stand 40, 4| which is composed of suitable material in the form of a plate 42 from which depend conical legs 43 which space the plate 42 above the respective platform and permit free circulation of the gases under the plate 42.

Imposed on each annealing stand is a respective cover 44, 45 enclosing a respective stack 46, 41 of the sheet material being treated and annealed, in the manner and form already disclosed in my above mentioned prior patent,

wherein each cover is provided on its sides with downwardly tapering flanges 48 which have attached to the outer lower edge thereof the sand retaining rim 49 which retains a quantity of sand or the like 50 to absolutely prevent passage of any air or fluids between the top of the stand and the lower edge of the cover, thereby preventing the possibility of any oxidizing of the contents of the cover.

In accordance with the present invention the burner openings II are re-located and placed in the hood instead of in the base, as in the said patent, so as to achieve among'other advantages, the feature of having the burner openings in the hood so as to be transportable with the hood instead of being in the base and remaining in the base when the hood is transported as is the case with the arrangement shown in the said patent.

In accordance with the present invention the burners playing into the combustion chambers through the burner openings ll fill the interior of the combustion chambers'with gases and products of combustion, and these products of combustion rise in the combustion chambers and pass into the elevated openings in the radially outward side of the upper partition section 20 of the tiers and then pass downwardly through the bores of the tiers to and through the openings 52 which are on a level with the lower side of the plates 4| of the annealing stands and are larger than the openings 53; and some of the gases moving in thebores of the tiers pass upwardly and into the upper part of the annealing chamber through the elevated openings 53. This arrangement or distribution of the heating gases not only provides proper circulation of the hot gases at the lower part of the combustion chamber, but the provision of the elevated openings 53 in the upper parts of the partitions provide for distribution of the hot gases at the upper part of the annealing chamber, thereby effecting a much improved distribution of the gases procuring greater heating efficiency and greater uniformity of heat in the annealing chamber.

The partitions being of heat resisting metal or of refractory material suitable to conduct and radiate heat, the heat in the combustion chamhers is embodied in the partition and radiated into the annealing chamber, so that the annealing chamber has heat radiated therein for the full height thereof not only by conduction through the partitions, but also by convection by reason of the movement of the gases into the annealing chamber through the partition openings 52 and 53. The present form of the tiers composing the partitions is such as to present a maximum surface area absorbing, conducting and radiating heat from the combustion chamber to the annealing chamber. The form and arrangement of the tiers also provide'for expansion and ,contraction, and the method of mounting the sections into tiers, and the tiers into partitions enables easy removability thereof for replacement when necessary.

It is desired to expressly mention as within thescope of the invention the elongation of the furnace shown and described herein to any suitable length and size, and the provision of any desired or suitable number of burner openings and fines and'fiue openings, and stands enabling materials, and in the structure and arrangement of the parts, within the spirit of the invention and the scope of the subjoined claims.

What is claimed is:

1 An annealing furnace comprising a base -provided centrally with exhaust openings, a hood resting on said base and formed in the side wall thereof with burner openings, tubular vertical partitions inrsaid hood, said partitions being arranged relative to said. hood to define combustion chambers in direct communication with said burner openings and an annealing chamber in direct communication with said exhaust openings, said partitions being formed with first openings adjacent their upper ends whereby communication is established between said .combustion chambers and the interior of said partitions, said partitions being formed with vertically spaced second and third openings establishing communication between the interior of the partitions and said annealing chamber, said second openings being located adjacent the upper end of said partitions so as to positively circulate the products of combustion over and around any material spacedly supported on said base in said annealing chamber, said third openings being located adjacent the lower end of said partitions soas to circulate additional products of combustion around and under the lower part of the material in the annealing chamber, whereby uniform heating of the material is procured.

2. In an annealing furnace, a base provided centrally with exhaust openings, a hood resting on said base and formed in the side wall thereof with burner openings, tubular vertical partitions in said hood, said partitions being arranged relative to said hood to define combustion chambers in direct communication with said burner openings and an annealing chamber in direct communication with said exhaust openings, said partitions beingformed with first openings adjacent" their upper ends ,whereby communication is established between said combustion chamber and the interior of said partitions, said parti-' ,tions further being formed with vertically spaced second and third openings establishing communication between the interior of said partitions and said annealing chamber, said second openings being located adjacent the upper ends of said partitions so as to positively circulate the products of combustion over and around any material spacedly supported on said base in said annealing chamber, said third openings being located adjacent the lower ends of said partition so as to circulate additional products of combustion around and under the lower part of the material in the annealing chamber, said tubular vertical partitions comprising conduits of substantially triangular cross section each arranged with two sides exposed in said combustion chamber and the remaining side exposed nealing chamber.

3. An annealing furnace comprising a. base provided centrally with exhaust openings, a hood resting-on said base and formed in the side wall thereof with burner openings, tubular vertical partitions in said hood, said partitions being arranged relative to said hood to define combustion chambers in direct communication with said burner openings and an annealing chamber openings adjacent their upper ends whereby communication is established between'said com-- bustion chambers and the interior of said partiin said antions, said partitions being formed with vertically spaced second and third openings establishing communication between the interior of said partitions and said annealing chamber, said second openings being located adjacent the upper ends of said partitions so as to positively circulate the products of combustion over and around any material spacedly supported on said base in said annealing chamber, said third openings being located adjacent the lower ends of said partition so as to circulate additional prod- 4. An annealing furnace comprising a base provided centrally with exhaust openings, a hood resting on said base and formed in the side wall thereof with burner openings, tubular vertical partitions in said hood, said partitions being arranged relative to-said hood to define combustion chambers in direct communication with said burner openings and an annealing chamber in direct communication with said exhaust openings, said partitions being formed with first openings adjacent their upper ends whereby communication is established between said combus tion chambers and the interior of said partitions, said partitions further being formed with vertically spaced second and third openings establishing communication between the interior of said partitions and said annealing chamber,

said second openings being located adjacent the upper ends of said partitions so as to positively circulate the products of combustion over and around any material spacedly supported on said base in said annealing chamber said third openings being located adjacent the lower ends of said partitions so as to circulate additional products of combustion around and under the lower part of the material in the annealing chamber, said partitions comprising conduit means of substantially triangular cross section arranged with two sides thereof exposed in said combustion chambers and'with its remaining side exposed in said annealing chamber, said conduit means comprising a plurality of vertically superposed sections, assembling means traversing the sections and assembling the same, said assembling means comprising a vertical rod passing through the superposed sections and having a head on its lower .end acting as an abutment for the lower end of the lowermost section, the upper end of said rod traversing the top of the hood, and fastening means holding the upper end'of the rod and the upper end of the uppermost conduit section assembled relative to the top of the hood.;

' 5. An annealing furnace comprising 'a base provided centrally with exhaust openings, a hood resting on said base and formed in the side wall thereof with burner openings, tubular vertical I burner openings and an annealing chamber in direct communication with said exhaust openings, .said partitions being formed with first openings adjacent their upper ends whereby communication is established between said combustion chambers and the interior of said partitions, said partitions being further formed with vertically spaced second and third openings estab- 'posed in said combustion chambers and with their remainingside exposed in said annealing chamber, said conduit means being arranged in side by side relation with the edges of its annealing chamber side engaged with the similar edges of the adjacent conduit means on either side thereof.

6. An annealing furnace comprising a base provided centrally with exhaust openings, a hood resting on said base and formed in the side wall thereof with burner openings, tubular vertical partitions in said hood arranged relative to saidhood to define combustion chambers in direct communication with said burner openings and an annealing chamber in direct communication with said exhaust openings, said partitions being formed with first openings adjacent their upper ends whereby communication is established between said combustion chambers and the interior of said partitions, said partitions being further formed with vertically spaced second and third openings establishing communication between the interior of said partitions and said annealing chamber, said first openings being 10- cated adjacent the upper end of said partitions so as to positively circulate the products of combustion over and around any material spacedly supported on said base in said annealing chamber, said second openings being located adjacent the lower ends of said partitions so as to circulate additional products of combustion around and under the lower part of the material .in the annealing chamber, said vertical partitions comprising conduit means of substantially triangular cross section arranged with its apex and the adjacent two sides exposed in the combustion chambers and with the remaining side thereof exposed in said annealing chamber, adjacent ones of said conduit means thereof being arranged in side by side touching relation, the touching corners of said conduit means having complementary interlocking formations whereby relative shifting of said conduit means is prevented.

'7. An annealing furnace comprising a base provided centrally with exhaust openings, a hood resting on said base and' formed in the side walls thereof with burner openings, tubular, vertical partitions-in said hood, said partitions being arranged relative to said hood to define combustion chambers in direct communication with said burner openings and an annealing chamber in direct communication with said exhaust openings, said partitions being formed with first openings adjacent their upper ends whereby communication is established between said combustion chambers and the interior of said partitions, said partitions being further formed with vertically spaced second and third openings establishing communication between the interior of said partitions and said annealing chamber, said second openings being located adjacent the upper ends of said partitions so as to positively circulate the products of combustion over and around any material spacedly supported on said base in said annealing chamber, said third openings being CLARENCE B. HOAK. 

